In any offshore, hydrocarbon containing field such as one holding crude oil or gas, normally at least one platform or marine structure is installed at a judicious location within the known bounds of the field. The primary functions of such a platform are at least twofold. Operationally, it serves as a base for drilling the needed number of wells into the subterranean reservoir to tap into the stored hydrocarbons. Secondly it functions to receive, treat, and store hydrocarbons which are conducted from other wells within the same field.
Normally the other wells are dispersed about the field at sites where it is determined that the hydrocarbon source can be readily reached. Thus, any productive field will usually contain numerous wells disposed about the ocean floor at various distances from the main platform.
In either instance, each dispersed well is provided with a well head which is capable of regulating the flow of hydrocarbons therethrough. Further, each well is provided with a flow or pipeline which communicates the well with the main platform or with a supplementary fluid storing facility.
It is desirable in the instance of any offshore marine platform, that it be initially designed and fabricated to accommodate a predictable number of wells which will be drilled from the structure. This determination can be initially made only within specific limitations. However, subsequent to the platform being submerged and set at a working site, it cannot always be adjusted or modified to accommodate varying operating conditions which arise or develop over an extended period of time.
For example, the usual drilling type offshore platform is normally provided with a number of vertical drilling conductors. The latter extend from the platform deck to the ocean floor whereby to accommodate and guide a drill string. These conductors are preplaced within the platform and are supported by the jacket in such manner to be available to the movable drilling derrick and equipment, as well as to permit the maximum number of wells to be drilled.
As mentioned, the platform must also accommodate flow lines which communicate the dispersed various well heads with the separating and storage equipment on the platform itself. However, provision is not always made during the initial fabrication and installation of the structure to accommodate the total number of flow lines which will eventually be required. Each platform is provided nonetheless with a sufficient number of drilling conductors in contemplation of the subsequent drilling of wells or the connecting of flow lines which had not been initially planned for.
As a matter of practicality, the drilling conductors which comprise a relatively heavy walled steel tubing, are normally driven into the ocean floor and only receive lateral support from the jacket. The drilling conductors therefore normally extend for a considerable distance into the substrate beneath the platform.
What is presently provided is a means whereby the platform's drilling conductors can be adapted to and utilized for accommodating needed hydrocarbon carrying flow lines. This is achieved by altering one or more of the drilling conductors in situ subsequent to their installation at the operating site.
Physically, the platform jacket is adjusted by severing at least one of the drilling conductors at a point adjacent to the ocean floor. The parted conductor segments are then axially separated a sufficient distance to allow insertion of a prefabricated conduit bending segment into the formed gap.
The inserted segment is fastened into, and becomes integral with the conductor. A baffle means which is thereafter inserted into the conductor upper end defines discrete passages to accommodate a plurality of flexible flow lines or conduits which will subsequently be inserted to extend from the ocean floor to the platform's deck.
The baffle means is so positioned within the modified conductor to fix the relative positions of the various conduits. The baffle thereby precludes said conduits from becoming entangled or even certain ones from coming in contact one with the other.
It is therefore an object of the invention to provide a marine platform adapted to be altered after being installed at an offshore site, to accommodate a plurality of hydrocarbon carrying flow lines and necessary control lines.
A further object is to provide a marine platform or structure of the type contemplated, which is capable of being modified after being installed within a body of water thus to accommodate a greater volume of hydrocarbon flow.
A still further object is to provide a conduit deflecting means within a riser on a marine structure, which permits the insertion of flow lines between the structure's deck and the ocean floor in response to the need for added flow capacity.